how to tell if this shy girl likes me?

she is a lovely girl, i dont want to take things the wrong way and cause her to go back into her shell.

1. she used to be quiet before but now she loves to tease me. about anything and all the time. I would walk into a room and she will find something to say about me.

2. Sometimes if ive not said something to her and we are in a group she will say soemthing about me. for instance I teased her about betting on tennis and how its a bad girl thing to do. a week later she says to everyone while im there 'i was about to printscreen my last winnings cos apprenelty its bad'. Another time she joking said to another two girls while i was there and they were talking about who is in there lessons. She said 'ive got john in mine' (she is pretending she hates it).

3. Ive said some flirty things to her. and a mutaul friend said yeah she knows you like her. (this is good right as the shy girl still talks to me, still is playful).